11 billion would be 11,000 million.
Yes, a redshift of 2.18 does equal to a light travel distance of nearly 11 billion years (i.e. 10.7 billion years).
10 to the power of 11 = 100 billion
Expressed in figures, this is equal to 11,000,000,000.
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11 zeros is the same as one zero. They are both equal to 0.
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